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OBJECTIVES: Current approaches for evaluating noise-induced hearing loss (NIHL), such as the International Standards Organization 1999 (ISO) 1999 prediction model, rely mainly on noise energy and exposure time, thus ignoring the intricate time-frequency characteristics of noise, which also play an important role in NIHL evaluation. In this study, an innovative NIHL prediction model based on temporal and spectral feature extraction using an asymmetric convolution algorithm is proposed. DESIGN: Personal data and individual occupational noise records from 2214 workers across 23 factories in Zhejiang Province, China, were used in this study. In addition to traditional metrics like noise energy and exposure duration, the importance of time-frequency features in NIHL assessment was also emphasized. To capture these features, operations such as random sampling, windowing, short-time Fourier transform, and splicing were performed to create time-frequency spectrograms from noise recordings. Two asymmetric convolution kernels then were used to extract these critical features. These features, combined with personal information (e.g., age, length of service) in various configurations, were used as model inputs. The optimal network structure was selected based on the area under the curve (AUC) from 10-fold cross-validation, alongside the Wilcoxon signed ranks test. The proposed model was compared with the support vector machine (SVM) and ISO 1999 models, and the superiority of the new approach was verified by ablation experiments. RESULTS: The proposed model had an AUC of 0.7768 ± 0.0223 (mean ± SD), outperforming both the SVM model (AUC: 0.7504 ± 0.0273) and the ISO 1999 model (AUC: 0.5094 ± 0.0071). Wilcoxon signed ranks tests confirmed the significant improvement of the proposed model ( p = 0.0025 compared with ISO 1999, and p = 0.00142 compared with SVM). CONCLUSIONS: This study introduced a new NIHL prediction method that provides deeper insights into industrial noise exposure data. The results demonstrated the superior performance of the new model over ISO 1999 and SVM models. By combining time-frequency features and personal information, the proposed approach bridged the gap between conventional noise assessment and machine learning-based methods, effectively improving the ability to protect workers' hearing.
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Perda Auditiva Provocada por Ruído , Ruído Ocupacional , Doenças Profissionais , Exposição Ocupacional , Humanos , Ruído Ocupacional/efeitos adversos , ChinaRESUMO
Organic photothermal conversion materials hold immense promise for various applications owing to their structural flexibility. Recent research has focused on enhancing near-infrared (NIR) absorption and mitigating radiative transition processes. In this study, we have developed a viable approach to the design of photothermal conversion materials through the construction of ternary organic cocrystals, by introducing a third component as a molecular blocker and motion unit into a binary donor-acceptor system. Superstructural and photophysical properties of the ternary cocrystals were characterized using various spectroscopic techniques. The role of the molecular blocker in radical stabilization and photothermal conversion were demonstrated. Intriguingly, the motions of the entire pyrene molecules in the cocrystal have been observed by variable temperature single-crystal X-ray diffraction results. The excellent performance of ternary cocrystal as a photothermal material was validated through efficient NIR-II photothermal and solar-driven water evaporation experiments. The efficiency of water evaporation reached 88.7 %, with a corresponding evaporation rate of 1.29 kg m-2 h-1, representing excellent performance among pure organic small molecular photothermal conversion materials. Our research underscores the introduction of molecular blockers and motion units to stabilize radicals and produce outstanding photothermal conversion materials, offering new pathways for developing efficient and stable photothermal conversion materials.
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Molybdenum disulfide (MoS2) has been deemed as one of the promising noble-metal-free electrocatalysts for hydrogen evolution reaction (HER), but it suffers from the inert basal plane and low electronic conductivity. Regulating the morphology of MoS2during the synthesis on conductive substrates is a synergistic strategy for enhancing the HER performance. In this work, vertical MoS2nanosheets were fabricated on carbon cloth (CC) using an atmospheric pressure chemical vapor deposition method. The growth process could be effectively tuned through introducing hydrogen gas during vapor deposition process, resulting in nanosheets with increased edge density. The mechanism for edge-enriching through controlling the growth atmosphere is systematically studied. The as-prepared MoS2exhibits excellent HER activity due to the combination of optimized microstructures and coupling with CC. Our findings provide new insights to design advanced MoS2-based electrocatalysts for HER.
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Biophysical markers of cells such as cellular electrical and mechanical properties have been proven as promising label-free biomarkers for studying, characterizing, and classifying different cell types and even their subpopulations. Further analysis or manipulation of specific cell types or subtypes requires accurate isolation of them from the original heterogeneous samples. However, there is currently a lack of cell sorting ability that could actively separate a large number of individual cells at the single-cell level based on their multivariate biophysical makers or phenotypes. In this work, we, for the first time, demonstrate label-free and high-throughput acoustic single-cell sorting activated by the characterization of multivariate biophysical phenotypes. Electrical phenotyping is implemented by single-cell electrical impedance characterization with two pairs of differential sensing electrodes, while mechanical phenotyping is performed by extracting the transit time for the single cell to pass through microconstriction from the recorded impedance signals. A real-time impedance signal processing and triggering algorithm has been developed to identify the target sample population and activate a pulsed highly focused surface acoustic wave for single-cell level sorting. We have demonstrated acoustic single-particle sorting solely based on electrical or mechanical phenotyping. Furthermore, we have applied the developed microfluidic system to sort live MCF-7 cells from a mixture of fixed and live MCF-7 population activated by a combined electrical and mechanical phenotyping at a high throughput >100 cells/s and purity â¼91.8%. This demonstrated ability to analyze and sort cells based on multivariate biophysical phenotyping provides a solution to the current challenges of cell purification that lack specific molecular biomarkers.
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Acústica , Técnicas Analíticas Microfluídicas , Impedância Elétrica , Citometria de Fluxo , Humanos , Microfluídica , Análise de Célula Única , SomRESUMO
Cellular mechanical phenotypes in connection to physiological and pathological states of cells have become a promising intrinsic biomarker for label-free cell analysis in various biological research and medical diagnostics. In this work, we present a microfluidic system capable of high-throughput cellular mechanical phenotyping based on a rapid single-cell hydrodynamic stretching in a continuous viscoelastic fluid flow. Randomly introduced single cells are first aligned into a single streamline in viscoelastic fluids before being guided to a flow splitting junction for consistent hydrodynamic stretching. The arrival of individual cells prior to the flow splitting junction can be detected by an electrical sensing unit, which produces a triggering signal to activate a high-speed camera for on-demand imaging of the cell motion and deformation through the flow splitting junction. Cellular mechanical phenotypes, including cell size and cell deformability, are extracted from the analysis of these captured single-cell images. We have evaluated the sensitivity of the developed microfluidic mechanical phenotyping system by measuring the synthesized hydrogel microbeads with known Young's modulus. With this microfluidic cellular mechanical phenotyping system, we have revealed the statistical difference in the deformability of microfilament disrupted, normal, and fixed NIH 3T3 fibroblast cells. Furthermore, with the implementation of a machine-learning-based classification of MCF-10A and MDA-MB-231 mixtures, our label-free cellular phenotyping system has achieved a comparable cell analysis accuracy (0.9:1, 5.03:1) with respect to the fluorescence-based flow cytometry results (0.97:1, 5.33:1). The presented microfluidic mechanical phenotyping technique will open new avenues for high-throughput and label-free single-cell analysis in diverse biomedical applications.
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Microfluídica , Análise de Célula Única , Animais , Citometria de Fluxo , Hidrodinâmica , Camundongos , Células NIH 3T3RESUMO
The surface of nanowires is a source of interest mainly for electrical prospects. Thus, different surface chemical treatments were carried out to develop recipes to control the surface effect. In this work, we succeed in shifting and tuning the semiconductivity of a Si nanowire-based device from n- to p-type. This was accomplished by generating a hole transport layer at the surface by using an electrochemical reaction-based nonequilibrium position to enhance the impact of the surface charge transfer. This was completed by applying different annealing pulses at low temperature (below 400 °C) to reserve the hydrogen bonds at the surface. After each annealing pulse, the surface was characterized by XPS, Kelvin probe measurements, and conductivity measured by FET based on a single Si NW. The mechanism and conclusion were supported experimentally and theoretically. To this end, this strategy has been demonstrated as an essential tool which could pave a new road for regulating semiconductivity and for other low-dimensional nanomaterials.
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Droplet-based single-cell sequencing has emerged as a very powerful tool to study the cellular heterogeneity in diseased tissues for a variety of biological problems. However, the current droplet generation with a single particle and cell encapsulation is a random process and suffers from a low yield that is unable to fulfill the high-throughput analysis requirement. In this work, we present a new fluorescence-activated droplet sorting (FADS) system that can isolate single-cell droplets at high accuracy and high yield using a highly focused surface acoustic wave (HFSAW) with a beam width around 50 µm. The acoustic wave is locally coupled into the microfluidic channel for droplet sorting through a micropillar waveguide structure between the channel and the interdigitated transducer (IDT). This detachable acoustic sorting system allows the disposal of the microfluidic channel after a single use to avoid cross-contamination and keeps the expensive IDT device reusable. We have achieved rapid and accurate isolation of single-cell droplets with purity higher than 90% at â¼1 kHz sorting rate with three different encapsulation contents. In addition, with the uniformly produced droplet size at â¼40 µm, the present acoustic FADS system enables effective sorting of small particles down to submicrometer size, which is challenging for existing fluorescence-activated cell sorting systems.
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Citometria de Fluxo/métodos , Som , Desenho de Equipamento , Citometria de Fluxo/instrumentação , Humanos , Células MCF-7 , Técnicas Analíticas Microfluídicas , Análise de Célula ÚnicaRESUMO
In this work, we demonstrate a sheathless acoustic fluorescence activated cell sorting (aFACS) system by combining elasto-inertial cell focusing and highly focused traveling surface acoustic wave (FTSAW) to sort cells with high recovery rate, purity, and cell viability. The microfluidic sorting device utilizes elasto-inertial particle focusing to align cells in a single file for improving sorting accuracy and efficiency without sample dilution. Our sorting device can effectively focus 1 µm particles which represents the general minimum size for a majority of cell sorting applications. Upon the fluorescence interrogation at the single cell level, individual cells are deflected to the target outlet by a â¼50 µm wide highly focused acoustic field. We have applied our aFACS to sort three different cell lines (i.e., MCF-7, MDA-231, and human-induced pluripotent stem-cell-derived cardiomyocytes; hiPSC-CMs) at â¼kHz with a sorting purity and recovery rate both of about 90%. A further comparison demonstrates that the cell viability drops by 35-45% using a commercial FACS machine, while the cell viability only drops by 3-4% using our aFACS system. The developed aFACS system provides a benchtop solution for rapid, highly accurate single cell level sorting with high cell viability, in particular for sensitive cell types.
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Citometria de Fluxo/métodos , Técnicas Analíticas Microfluídicas , Acústica , Diferenciação Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Fluorescência , Humanos , Miócitos Cardíacos , Células-Tronco Pluripotentes , TemperaturaRESUMO
Alpine grasslands on the Qinghai-Tibet Plateau (QTP) play an essential role in water conservation, biodiversity protection and climate feedback, with aboveground biomass (AGB) serving as a crucial indicator of grassland health and functionality. While previous studies have independently explored the phenological differences, cumulative effects, and spatial variability of climatic impacts on biomass/productivity in alpine grasslands, the cascading effects regarding climate and phenology on AGB still present knowledge gaps. Here, using peak AGB measurements, remote sensing and gridded climate data in the QTP alpine grasslands during 2002-2018, we systematically analyzed the impact paths of climatic variables (i.e., cumulative precipitation, CP; growing degree-days, GDD) and phenology-mediated paths (start and peak date of the growing season, SOS and POS) on AGB and their regional differences. During the preseason (pre60) or the growing season (sos-pos), climate primarily directly impacted variations in AGB across different climatic regions, although a phenology-mediated path by which climate indirectly affected AGB existed (i.e., GDDsos-pos â POS â AGB). Three general patterns were revealed: In the plateau temperate arid regions, an increase in CPpre60 significantly promoted AGB (path coefficients w = 0.61-0.71), whereas an increase in GDDpre60 inhibited AGB (w = -0.42 ~ -0.49); In the plateau sub-cold regions, increases in both CPsos-pos and GDDsos-pos significantly promoted AGB, respectively (w = 0.46-0.81 and w = 0.37-0.70); Similarly, in the plateau temperate arid or semi-arid regions, increases in CPsos-pos also significantly promoted the AGB (w = 0.56-0.73). This study highlights that the water and heat accumulation mainly exert direct impacts on alpine grassland AGB across various climatic regions and phenological stages, providing insights into the mechanism driving AGB by climate and phenology during spring and summer.
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Biomassa , Mudança Climática , Pradaria , Tibet , Monitoramento Ambiental , Clima , Estações do AnoRESUMO
This work investigated the impact of periodic thickness and doping region on the doping efficiency of the P-type AlGaN superlattice. In this paper, the band structure of the simulated superlattice was analyzed. The superlattice structure of Al0.1Ga0.3N/Al0.4Ga0.6N, and the AlGaN buffer on the sapphire substrate, achieved a resistivity of ~3.3 Ω·cm. The results indicate that barrier doping and low periodic thickness offer significant advantages in introducing a reduction of the resistivity of P-type AlGaN superlattice structures.
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In this study, we propose a polarized electron blocking layer (EBL) structure using AlxGa1-xN/AlxGa1-xN to enhance the internal quantum efficiency (IQE) of AlGaN-based ultraviolet light-emitting diodes (UV LEDs). Our findings indicate that this polarized EBL structure significantly improves IQE compared to conventional EBLs. Additionally, we introduce an electric-field reservoir (EFR) optimization method to maximize IQE. Specifically, optimizing the polarized EBL structure of AlxGa1-xN/AlxGa1-xN enhances the hole drift rate, resulting in an IQE improvement of 19% and an optical output power increase of 186 mW at a current of 210 mA.
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Growing evidences indicate that RNA-binding proteins (RBPs) play critical roles in regulating the RNA splicing, polyadenylation, stability, localization, translation, and turnover. Abnormal expression of RBPs can promote tumorigenesis. Here, we performed a CRISPR screen using an RBP pooled CRISPR knockout library and identified 27 potential RBPs with role in supporting colorectal cancer (CRC) survival. We found that the deletion/depletion of INTS3 triggered apoptosis in CRC. The in vitro experiments and RNA sequencing revealed that INTS3 destabilized pro-apoptotic gene transcripts and contributed to the survival of CRC cells. INTS3 loss delayed CRC cells growth in vivo. Furthermore, delivery of DOTAP/cholesterol-mshINTS3 nanoparticles inhibited CRC tumor growth. Collectively, our work highlights the role of INTS3 in supporting CRC survival and provides several novel therapeutic targets for treatment.
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Cell-free protein synthesis (CFPS) with flexibility and controllability can provide a powerful platform for high-throughput screening of biomolecules, especially in the evolution of peptides or proteins. In this chapter, the emerging strategies for enhancing the protein expression level using different source strains, energy systems, and template designs in constructing CFPS systems are summarized and discussed in detail. In addition, we provide an overview of the ribosome display, mRNA display, cDNA display, and CIS display in vitro display technologies, which can couple genotype and phenotype by forming fusion complexes. Moreover, we point out the trend that improving the protein yields of CFPS itself can offer more favorable conditions for maintaining library diversity and display efficiency. It is hoped that the novel CFPS system can accelerate the development of protein evolution in biotechnological and medical applications.
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Proteínas , Ribossomos , Proteínas/análise , Biblioteca Gênica , Ribossomos/genética , Ribossomos/química , Ribossomos/metabolismo , Biossíntese de Proteínas/genética , DNA Complementar/análise , DNA Complementar/química , DNA Complementar/metabolismo , Sistema Livre de Células/química , Sistema Livre de Células/metabolismoRESUMO
Strict on-demand control of protein synthesis is a crucial aspect of synthetic biology. The 5'-terminal untranslated region (5'-UTR) is an essential bacterial genetic element that can be designed for the regulation of translation initiation. However, there is insufficient systematical data on the consistency of 5'-UTR function among various bacterial cells and in vitro protein synthesis systems, which is crucial for the standardization and modularization of genetic elements in synthetic biology. Here, more than 400 expression cassettes comprising the GFP gene under the regulation of various 5'-UTRs were systematically characterized to evaluate the protein translation consistency in the two popular Escherichia coli strains of JM109 and BL21, as well as an in vitro protein expression system based on cell lysate. In contrast to the very strong correlation between the two cellular systems, the consistency between in vivo and in vitro protein translation was lost, whereby both in vivo and in vitro translation evidently deviated from the estimation of the standard statistical thermodynamic model. Finally, we found that the absence of nucleotide C and complex secondary structure in the 5'-UTR significantly improve the efficiency of protein translation, both in vitro and in vivo.
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In this paper, the X-ray diffraction full width at half the maximum (XRD FWHM) of a 3.5 µm-thick hydride vapor phase epitaxy-aluminum nitride (HVPE-AlN) (002) face after high-temperature annealing was reduced to 129 arcsec. The tensile strain in the HVPE-AlN samples gradually released with the increasing annealing temperature. When the annealing temperature exceeded 1700 °C, an aluminum oxynitride (AlON) region was generated at the contact interface between HVPE-AlN and sapphire, and the AlON structure was observed to conform to the characteristics of Al5O6N by high-resolution transmission electron microscopy (HRTEM). A 265 nm light-emitting diode (LED) based on an HVPE-AlN template annealed at 1700 °C achieved a light output power (LOP) of 4.48 mW at 50 mA, which was approximately 57% greater than that of the original sample.
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Accurate mapping spatiotemporal patterns of CO2 emissions and understanding its driving factors are very important, it is useful for the scientific and rational formulation of carbon emission reduction policies. Nevertheless, due to data availability issues, most studies have been limited to the global and national scales, and the models used were relatively simple. In this paper, we used the 500 m Visible Infrared Imaging Radiometer Suite Day/Night Band (VIIRS-DNB) data and the 250 m Moderate Resolution Imaging Spectroradiometer normalized difference vegetation index (MODIS NDVI) and proposed an improved CO2 emissions index (ICEI) to calculate CO2 emissions. Compared with the total nighttime light (NTL), the average regression coefficient (R2) can be improve from 0.73 to 0.78. We also used the coefficient of variation, spatial autocorrelation, and geographically weighted regression models to analyze the temporal and spatial variation mode of CO2 emissions, as well as the associated correlation and heterogeneity, at three different administrative unit scales during 2012-2019. Our experimental results demonstrate that: (1) the improved index (ICEI) is better than the traditional variable (NTL) in estimating CO2 emissions; (2) the highest CO2 emissions are primarily gathered in the developed coastal areas in eastern China; and (3) at the provincial level, the added value of the secondary industry is the most significant factor, whereas the added value of the tertiary industry is negatively correlated with CO2 emissions.
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Dióxido de Carbono , Imagens de Satélites , Carbono , Dióxido de Carbono/análise , China , Indústrias , Análise EspacialRESUMO
In this paper, the conditions of the dip-coating method of SiO2 nanospheres are optimized, and a neatly arranged single-layer SiO2 array is obtained. On this basis, a "top-down" inductively coupled plasma (ICP) technique is used to etch the p-GaN layer to prepare a periodic triangular nanopore array. After the etching is completed, the compressive stress in the epitaxial wafer sample is released to a certain extent. Then, die processing is performed on the etched LED epitaxial wafer samples. The LED chip with an etching depth of 150 nm has the highest overall luminous efficiency. Under a 100 mA injection current, the light output power (LOP) of the etched 150 nm sample is 23.61% higher than that of the original unetched sample.
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Non-small cell lung cancer remains the leading cause of cancer-related deaths worldwide with high morbidity and mortality. There is an urgent need to reveal new molecular mechanisms that contribute to NSCLC progression to facilitate drug development and to improve overall survival. Much attention has been paid to the role of circRNAs in NSCLC development. However, the knowledge of circRNAs in NSCLC is still limited, and need to be further explored. The dysregulation of circACC1 was evaluated by qRT-PCR in NSCLC samples and cell lines. The oncogenic role of circACC1 in NSCLC progression was analyzed by CCK8 and colony formation assays. The interaction between the circACC1 and miR-29c-3p, as well as MCL-1, was verified by qRT-PCR, Western blot, luciferase reporter assay, and RIP experiment. Elevated levels of circACC1 were found in NSCLC patients and were negatively correlated with OS. Ectopic expression of circACC1 promoted the capacity of cell growth and clonogenicity, while the inhibition of circACC1 decreased the proliferation and clonogenicity potential. Mechanism studies elucidated that circACC1 contributes to cell growth via directly binding to miR-29c-3p. Transfection of miR-29c-3p mimic blocked circACC1 mediated NSCLC cell proliferation. MCL-1 is a downstream target of miR-29c-3p in NSCLC cells. The circACC1/miR-29c-3p/MCL-1 axis is important in NSCLS proliferation.
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Gemcitabine (GEM) and its derivatives of deoxycytosine is a promising anticancer candidate which is effective for the treatment of various cancers including lung cancer via cascade targetting Erk/Mek/Raf/Ras pathway and blocking the proliferation of the tumor cells. In this present work, we have described reduced graphene oxide (rGO) in the presence of anticancer utilizing ascorbic acid as reducing agents for lung cancer treatment. GEM reduced graphene oxide (termed as GEM-rGO) has resulted in a smooth and transparent morphological surface, which was confirmed by various spectroscopical investigations. The anticancer drug-loaded rGO has displayed remarkable cytotoxic activities against a panel of lung cancer cell lines when compared to the untreated lung cancer cells. Further, we examined the morphological observation of the cancer cell death was monitored through the fluorescence microscopic examinations. In addition, the cell deaths of the lung cancer cells were observed by the flow cytometry analyses. In addition, the non-toxic nature of potent GEM-rGO and GEM-rGO + NIR was confirmed by in vivo systemic toxicity analysis. Besides, the higher safety feature of the GEM-rGO and GEM-rGO + NIR was evidenced by histological analyses of the mice organs. The subcutaneous injection of GEM-rGO and GEM-rGO + NIR into mice bearing A549 xenografts more effectively inhibited the tumor than the free GEM. Based on the outcomes, we can summarise that the GEM reduced graphene oxide (GEM-rGO) can be used as a promising drug candidate for the treatment of lung cancer in the future.
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Antineoplásicos/química , Desoxicitidina/análogos & derivados , Grafite/química , Neoplasias Pulmonares/terapia , Células A549 , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Desoxicitidina/química , Desoxicitidina/farmacologia , Feminino , Grafite/farmacologia , Humanos , Raios Infravermelhos , Masculino , Camundongos , Neoplasias Experimentais , Terapia Fototérmica , GencitabinaRESUMO
Membranous nephropathy (MN), an autoimmune glomerular disease, is one of the most common causes of nephrotic syndrome in adults. In current clinical practice, the diagnosis is dependent on renal tissue biopsy. A new method for diagnosis and prognosis surveillance is urgently needed for patients. In the present study, we recruited 66 MN patients before any treatment and 11 healthy control (HC) and analyzed multiple aspects of the immunoglobulin heavy chain (IGH) repertoire of these samples using high-throughput sequencing. We found that the abnormalities of CDR-H3 length, hydrophobicity, somatic hypermutation (SHM), and germ line index were progressively more prominent in patients with MN, and the frequency of IGHV3-66 in post-therapy patients was significantly lower than that in pre-therapy patients. Moreover, we found that the IGHV3-38 gene was significantly related to PLA2R, which is the most commonly used biomarker. The most important discovery was that several IGHV, IGHD transcripts, CDR-H3 length, and SHM rate in pre-therapy patients had the potential to predict the therapeutic effect. Our study further demonstrated that the IGH repertoire could be a potential biomarker for prognosis prediction of MN. The landscape of circulating B-lymphocyte repertoires sheds new light on the detection and surveillance of MN.